2G Idle AFR

[morelock]

during clod starts i have to start my car twice it fire right up then dies, the second time its starts right up and runs good my afr stays at about 14.7.1 for about 30 seconds. Then my afr starts falling down it goes past 18.0.1 so i don't know where it is at actually and it starts sputtering really bad once it warms up it idles good but my afr never come above 17.4.1 at idle. im not sure what the afr should be at i don't have any tuning capability's yet waiting on the funds for ecmlink. she has a new isc and o2 sensor. any ideas thanks

 

[Absit]

When the engine is cold (<180*) it doesn't use the front O2 sensor for fuel calculations. Your profile shows an SAFC, is that not right?

 

[tifsim]

Your car might have leaky fuel injectors or your car may be leaking fuel pressure out somewhere in the system. That may be the issue at start up anyways. AFR's are pretty high though. When is the last time its had a fuel filter done on it?

 

[morelock]

no i had to take the safc out haven updated my profile yet sorry about that. i replaced the fuel filter about 2 weeks ago. if i had leaky fuel injector wouldn't it be running really rich its running so lean it doesn't want to run when its cold. i heard that the afr at idle should be around 14.1.1 is that right or am i way off?

 

[tifsim]

You could be sucking air in around your injectors and the fuel not making it to the cylinders because its leaking around the injectors on the intake instead of going where its supposed to be.

 

[morelock]

ok ill order new injector seals and see where that takes me hopefully it fixes it

 

[tifsim]

ok ill order new injector seals and see where that takes me hopefully it fixes it

Well i would at least look around the injectors and see if its wet around them before i ordered them.

 

[morelock]

ok ill check that out tomorrow if they are good would you have any idea of whet else it could be if thats not it?

 

[tifsim]

Check it out tomorrow and go from there, but my car hated having leaky injector seals. I had to turn the key on and off a couple times before it would actually start. Installed the new seals and it was good to go.

Now when it comes to your AFR, are you going off of your idling AFR? What are u reading your AFR with? Idling i wouldn't worry to much about, but driving it I would hate to see numbers like 18 if your using a wide band to read your AFR. I never actually read my AFR when i was reving the car with it sitting still either, I always monitored my car with a load on it while it was driving or on a dyno.


Wow i must be getting tired. Just reread the post and your worried about the idle AFR. I myself like my car running a little lean at idle. So I wouldn't worry about idle concentrate on the car being loaded or in action.

 

[morelock]

i have a aem ugo my afrs are between 14.1 to 16.9 just riding around, and 11.8 at wotso i think that that is ok. the only reason im worrying about it is because its a pain in the ass to get it to warm up when its firs started when its cold. i can let it warm up and kill it for like 20 min get in it and start it and it runs just fine its just when its cold its like it leans out so bad that it just doesnt want to run at all.

 

[Absit]

I assume you've checked for exhaust leaks before the WBO2 sensor?

 

[morelock]

ya the exhaust is about a month old no leaks at all. my external waste gate dump comes back into the exhaust after the o2 though if that will make any difference

 

[iBoostDSM]

Did you happen to ever figure out what it was, I'm having the same sort of problem. When I start my car it idle with AFR of about 14.7 but then after about 30 sec my exhaust starts popping and stuttering and I have an AFR of 17.5 - over 18. I still might have boost leaks I'm trying to fix though.

 

[taylor hindman]

I know that if you have a 255 wally and a bad stock fuel pressure regulator it will run like crap and it will also make your injectors fail sooner. well thats what happened to me anyways.